Cabochons

A cabochon is a gemstone that has been shaped and polished as opposed to being faceted. It typically has a smooth, convex top with a flat or slightly domed bottom. This form is especially common for opaque or translucent stones that do not take a good facet cut, or for stones that display color patterns, chatoyancy, or asterism.

Shape and cutting: The standard cabochon features a domed upper surface and a flat, slightly curved, or concave undersurface. Edges are smooth and the stone is polished to a high luster. The curvature and thickness vary with the material and intended use. The cutting process involves grinding and polishing with progressively finer abrasive wheels or laps.

Materials and examples: Common cabochons come from agate, chalcedony, carnelian, jasper, onyx, lapis lazuli, malachite, moonstone, turquoise, and opal. Opal is frequently cut en cabochon to display its play of color. Stones with chatoyancy (such as tiger’s eye), color zoning, or star effects are often cut cabochon to maximize these visual phenomena.

Uses: Cabochons are widely used in jewelry, including rings, pendants, earrings, and brooches, as well as inlays for mosaics and decorative objects. They are favored when the stone’s color, pattern, or optical effect is best shown on a smooth dome rather than a facets layout.

History and terminology: The term cabochon derives from the French caboche, meaning “head” or “dome.” The technique has ancient roots and remains popular for certain stones and aesthetics where faceting is less suitable.

Care and value: Care depends on the material; many cabochons are relatively soft or porous and require gentle cleaning. Value depends on the material, color, pattern, and the quality of the dome and polish.